The difference in the valve length isn't huge. I think about .060. If this is a mild build and single springs I wouldnt worry about it. If this is a race effort, I'd suggest using stainless nail head valves anyway.

Well, art is art, isn't it? Still, on the other hand, water is water! And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now, uh... Now you tell me what you know.